Dime Store (address and info)
This is the kind of happy hour that involves more advanced math than most people are probably capable of once they get real deep into the happy hour itself, but it goes like this: on Tuesday through Friday from 3-6pm, you'll get 50% off alcohol from 3-4pm, 40% off alcohol for 4-5pm, and 30% off alcohol from 5-6pm. This is the law of diminishing returns of happy hours, so get there early to get the most value.
Downtown Louie's Lounge (address and info)
Grand Circus Park
Monday through Friday from 3-6pm, get $2 domestic bottled beer (excludes craft beers, boooo), $2 Bud Light pints, and $3 tallboys. There are also $5 wines & well pours, and $2 off all appetizers.
Roast (address and info)
Perhaps you've heard that Roast's happy hour was once the most famous happy hour in Detroit? And that's still more or less true. Happy hour is Monday through Friday from 4-6:30pm: select wines & beers are $4, well drinks are $5. Plus, starting at 4:30pm, you get half off everything on the bar menu, which includes the famous Roast Burger, and the less famous, but equally delicious, chicken livers & creamy polenta. (Happy hour is only available in the bar.)